Gama, M. A. S.. Mariano, R. L. R., Viana, F. M. P, Ferreira, M. A. S. V., and Souza, E. B. 2011. Polyphasic characterization of pigmented strains of Xanthomonas pathogenic to cashew trees. Plant Dis. 95:793-802.The export of cashew {Anacardium occidentale) nuts generates millions of dollars for the Brazilian economy annually. However, production may be limited by the occurrence of diseases that affect cashew trees, such as Xanthomonas spot and angular leaf spot, which are caused by pigmented strains of Xantlummim.s and Xanthomonas ci tri pv. anacardii, respectively. Thirty-one pigmented strains o'i Xanthomonas were characterized for phenotypic, pathogenic, and molecular attributes. These strains were similar to X. citri pv. anacardii in phenotypical characteristics, sensitivity to antibiotics and copper compounds used in agriculture, epidemiology, and repetitive sequence-based polymerase chain reaction (rep-PCR) profiles. When inoculated into Brazilian pepper, cashew, mango, and hog plum seedlings, the pigmented strains of Xanthomonas and X. citri pv. anacardii produced similar symptoms. However, the pigmented strains of Xanthomonas were more aggressive toward cashew plants than toward the other hosts tested, which confirms their specificity. We conclude that pigmented strains oí Xanthomonas are very aggressive on cashew trees and should not be considered casual pathogens of these hosts. Moreover, based on our results from rep-PCR and IS/595-PCR amplification, we suggest that these strains constitute a variant of X. citri pv. anacardii.The production of cashew nuts (Anacardium occidentale L.) in Brazil is traditionally intended for the international market (14). In 2(K)7, exports of cashews ready for consumption reached 51 thousand tons, generating approximately 225 million U.S. dollars for the Brazilian economy (6). This production may be compromised by the many diseases aflecting cashew trees, including Xanthomonas spot caused by Xanthomonas campestris pv. niangiferaeindicae (Patel et al.) Robbs et al. (pigmented strains oí Xanthomonas) (29-32) and angular leaf spot caused by Xanthomonas citri pv. anacardii (Patel et al.) Ah-You et al. (1,2).X. campestris pv. mangiferaeindicae was originally reported causing mango (Mangifera indica L.) bacterial black spot in South Africa hy Doidge (5), and was natned Bacillus mangijera Doidge. In 1948, similar sytnptoms were ob.served in mango leaves and fruit in India by Patel et al. (16,17), who proposed the creation of a new species, Pseudomonas mangiferae-indicae Patel et al., because of differences observed between these strains and those from South Africa. Additionally, the authors described the pathogenicity of this bacterium in cashew trees without any further reports on its occurrence in nature or studies on its pathosysteni. In 1974, this species was renatned Xanthomonas campestris pv. mangiferaeindicae by Robbs ef al. (23). Interestingly, while both pigmented and nonpigmented strains of this bacterium have been isolated from mango trees with symptoms of bacterial bl...